This invention relates to a recording apparatus, a file management method, a program for a file management method, and a recording medium having a program for a file management method recorded thereon and can be applied typically to an optical disk apparatus.
In recent years, disk apparatus and the like have been proposed, which use a randomly accessible recording medium having a large capacity such as an optical disk to record an image pickup result.
A method is disclosed, for example, in Japanese Patent Laid-open No. 2001-84705 (hereinafter referred to as Patent Document 1), which uses such a disk apparatus as described above to improve the operability in operation of a large number of files. According to the method of the Patent Document 1, an index file for indexing a large number of files recorded on a recording medium is produced from the large number of files and recorded on the recording medium. The large number of files on the recording medium can be operated using the index file.
Japanese Patent Laid-open No. 2002-278996 (hereinafter referred to as Patent Document 2) discloses a method, which further improves the operability in operation of a large number of files recorded on a recording medium. According to the method of the Patent Document 2, an index file produced in such a manner as described above manages the files hierarchically.
In the methods described above, an index file is composed of a part of actual data, which collectively includes extract information formed by extracting information relating to a management object file and so forth and another part of management data, which collectively includes position information and so forth necessary for accessing to the actual data.
Referring to FIGS. 18A to 18D, the actual data part is composed of a sound entry E1, a text entry E2, a thumbnail picture entry E3, and a property entry E4, which are data sets collectively including extract information classified for individual types into groups. The sound entry E1 has allocated thereto a disk title and extract information of audio data for a short period of time representative of contents of management object files. The sound entry E1 includes a sound entry header SH set at the top thereof and representing that the entry is the sound entry E1 and a sequence of sound entry slots SES0, SES1, SES2, . . . each including extract information collected as a block.
The text entry E2 has allocated thereto the disk title and extract information of a character sequence of management object files. The text entry E2 includes a text entry header TXH set at the top thereof and representing that the entry is the text entry E2 and a sequence of text entry slots TXES0, TXES1, TXES2, . . . each including extract information collected as a block.
The thumbnail picture entry E3 has allocated thereto the disk title and extract information of still pictures representative of contents of the management object files. The thumbnail picture entry E3 includes a thumbnail picture entry header THH set at the top thereof and representing that the entry is the thumbnail picture entry E3 and a sequence of thumbnail picture entry slots THES0, THES1, THES2, . . . each including extract information collected as a block.
In contrast, the property entry E4 has allocated thereto the disk title and data representative of properties of the management object files and has allocated thereto extract information of binary data, which are set to the management object files. The property entry E4 includes a property entry header PH set at the top thereof and representing that the entry is the property entry E4 and a sequence of property entry slots PES0, PES1, PES2, . . . each including extract information collected as a block.
Consequently, for example, when a desired file is to be selected with reference to thumbnail pictures, when a file is to be selected based on titles, or in some other case, the index file can provide extract information set to a corresponding one of the entries E1 to E4 to the user in accordance with a selection criterion of the user so that the user can select a desired file simply, easily, and with certainty.
Incidentally, it is expected that, if the slots SES0, . . . , TXES0, . . . , THES0, . . . , and PES0, . . . of the sound entry E1, text entry E2, thumbnail picture entry E3, and property entry E4 of the index file having such a configuration as described above are formed with a fixed length, then it is possible to eliminate wasteful use of a recording medium when recording/deletion onto/from the recording medium are repeated and prevent a drop of the processing speed effectively.
Where the slots SES0, . . . , TXES0, . . . , THES0, . . . , and PES0, . . . are formed with a fixed length in this manner, depending upon a file of a management object, extract information obtained from the single file is allocated to and managed with a plurality of slots. Accordingly, it is necessary to manage a relationship between the slots.
Further, since the extract information is information obtained by extraction from the management object file, depending upon the type of the management object file, also such a situation possibly occurs that, although a corresponding slot is present in the property entry E4, no corresponding slot is present in some other entry or entries. Consequently, also it is possible to manage a relationship between the property entry E4 and the other entries E1 to E3.
Thus, it is expected that, if management information representative of relationships of the property entry E4 with the other entries is recorded in the property entry E4 and other slots recorded in the other entries E1 to E3 are referred to in accordance with the management information as indicated by arrow marks in FIGS. 18A to 18D, then the management of the extract information can be simplified.
On the other hand, where files recorded on a recording medium are managed with such an index file as described above, it is necessary to update the index file when a management object file or files are deleted or added. In this instance, if a corresponding slot or slots are not deleted or added actually but are set as free or empty slots and then the free or empty slots set in this manner are re-utilized, then useless use of regions on the recording medium can be reduced.
It is a possible idea to provide, in such setting of free slots and management of free slots for re-utilization as just described, a space bit map for management of free slots in each of the entries E1 to E4 and further set a link list, which is a list of information indicative of succeeding free slots.
However, where free slots are managed for each entry in this manner, there is a problem that, when the records of the four entries are brought out of matching with each other because of an a bend such as a result of a drop of the power supply before the index file is rewritten completely, a process for restoring the matching is complicated. Further, increased time is required for processing of the index file upon such deletion or addition of a file or files as described above, and this gives rise to a problem that increased processing time is required for a recording apparatus, which involves comparatively long access time such as an optical disk apparatus.
Thus, it is expected that, if such free slots as described above are managed collectively using the property entry, then such problems as described above can be eliminated. Therefore, it is demanded in collective management with the property entry to cope with deletion and addition of extract information by deletion, addition and so forth of a file or files.